In recent years, digital television broadcasting using satellites or cable broadcasting is becoming popular. With realization of this digital broadcasting, expectations rise for further new development including improvement in broadcast image and audio qualities, increases in the number of types of programs and the information amount using a compression technique, provision of new services such as an interactive service, evolution of the reception form.
FIG. 17 is a block diagram showing the arrangement of a conventional digital broadcasting reception apparatus using satellite broadcasting.
In this reception apparatus, information transmitted by satellite broadcasting is received by an antenna 1, and the received television information is tuned and demodulated by a tuner 2 in a reception device 8. Then, the television information is subjected to error correction processing (not shown), and if necessary, to charging correspondence, descrambling processing, and the like. Various data multiplexed as the TV information are demultiplexed into individual data by a multiplexed-signal demultiplexing circuit 3. The demultiplexed data include image information, audio information, and other additional data. These demultiplexed data are decoded by a decoding circuit 4. Of the decoded data, the image information and audio information are converted into analog signals by a D/A conversion circuit 5. The image and audio are respectively displayed and output by a TV receiver 6 serving as an externally connected display device. Note that the additional data concerns various functions in order to function as program sub-data.
A satellite TV program is recorded and played back by a recording/playback device (DVD/VTR) 7. Examples of the recording/playback device 7 are a recordable/playbackable DVD (Digital Video Disk drive) and digital VTR. The reception device 8 and recording/playback device 7 are connected by a data bus and the like. The recording scheme in the recording/playback device 7 is a digital recording scheme which performs bitstream recording. Note that bitstream recording is not limited to the use of the DVD or digital VTR (e.g., D-VHS type VTR), but is also supported by a DVC which is another consumer digital recording scheme. For example, even a digital recording device using various disk media can record a digital television program by format transformation or the like, as needed.
However, as a general method of displaying a television program on a home television, an image transmitted from a broadcasting station is directly displayed in conventional ground wave broadcasting and even the above-described digital television broadcasting. Similarly, in playing back a television program recorded by a VTR, the recorded data is directly played back.
In other words, it is very difficult for the conventional technique to more effectively change the display form by the user in accordance with the situation in display of a television program, playback/display of a VTR, or the like. This function is an effective display method in the future during the course of increasing the numbers of channels and programs in the development of digital television broadcasting, and is considered to be one of indispensables in terms of addition of new functions. This function, however, has not been realized yet.
For example, as a display subject, a telop display for special news such as “earthquake news information”, which is important upon recording, is often insignificant in playing back the recorded television information by the recording/playback device 7, but the recorded information is displayed without any change.